diff --git a/python/sglang/srt/server_args.py b/python/sglang/srt/server_args.py
index 2be1c045a0bf..7c898a0144b0 100644
--- a/python/sglang/srt/server_args.py
+++ b/python/sglang/srt/server_args.py
@@ -2042,6 +2042,13 @@ def _handle_mamba_radix_cache(
                     == 0
                 ), f"For SSM models with extra buffer, either FLA_CHUNK_SIZE or page_size must be divisible by the other, got {FLA_CHUNK_SIZE=}, {self.page_size=}"
         elif not self.disable_radix_cache:  # no_buffer
+            if self.page_size is not None and self.page_size != 1:
+                logger.warning(
+                    f"{model_arch} with radix cache requires page_size=1 in the current "
+                    f"Mamba scheduling mode (no_buffer), but got {self.page_size}. "
+                    "Automatically setting page_size=1."
+                )
+                self.page_size = 1
             if self.speculative_algorithm is None:
                 logger.warning(
                     "Disabling overlap schedule since mamba no_buffer is not compatible with "